Brucellosis is a zoonotic disease caused by Brucella species. It has been estimated that more than 500,000 new cases of Brucellosis occur annually all around the world. Relapse of the disease is one of the most important challenges. The most important reason for the relapse of brucellosis is the survival of the bacteria inside the macrophages, which makes them safe from the immune system and disrupts drug delivery mechanism. The present study was performed to assess the effects of Doxycycline-loaded Solid Lipid Nanoparticles (DOX-SLN) on the Brucella melitensis inside macrophages. DOX-SLN was prepared using double emulsion method. The technological characterization of DOX-SLN, including particle size, zeta potential, polydispersity index (PDI), drug loading and encapsulation efficiency were used. Fourier-transform infrared spectroscopy (FTIR) and Differential scanning calorimetry (DSC) were used to assess the interactions between Nanoparticles (NPs) components and crystalline form of doxycycline. Moreover, the effect of DOX-SLN on the bacteria were compared with that of the doxycycline using various methods, including well diffusion, Minimum Inhibitory Concentration (MIC), and investigation of their effects on murine macrophage-like cells cell line J774A.1. The means of particle size, zeta potential, PDI, drug loading and encapsulation efficiency were 299 ± 34 nm, − 28.7 ± 3.2 mV, 0.29 ± 0.027, 11.2 ± 1.3%, and 94.9 ± 3.2%, respectively. The morphology of NPs were spherical with a smooth surface. No chemical reaction was occurred between the components. Doxycycline was located within NP matrix in its molecular form. The DOX-SLN significantly decreased the microbial loading within macrophages (3.5 Log) in comparison with the free doxycycline. Since the DOX-SLN showed better effects on B. melitensis enclosed in macrophages than the free doxycycline, it is recommended to use it for treating brucellosis and preventing relapse.

The main goals of medicine consist of early detection and effective treatment of different diseases. In this regard, the rise of exosomes as carriers of natural biomarkers has recently attracted a lot of attention and managed to shed more light on the future of early disease diagnosis methods. Here, exosome biogenesis, its role as a biomarker in metabolic disorders, and recent advances in state-of-art technologies for exosome detection and isolation will be reviewed along with future research directions and challenges regarding the manipulation and genetic engineering of exosomes for potential in vitro and in vivo disease diagnosis approaches.

Background: Bacteria are able to form biofilm on the biotic and abiotic surfaces which helps to protect themselves from deleterious conditions, predation, desiccation, and exposure to antibacterial substances. About 80% of bacterial infections are caused by those bacteria living in the biofilm. Pseudomonas aeruginosa, a gram-negative, non-fermentative bacillus, and the ubiquitous bacterium is an important opportunistic pathogen notorious for biofilm formation and is remarkably resistant against most antibiotics multiple front-line antibiotics, which significantly contributes to eradication failure. The aim of this paper was to evaluate the anti-biofilm formation activity of Ag@PPEs gainst P. aeruginosa bacteria. Methods: An aqueous extract of black pomegranate peel was used for the synthesis of silver nanoparticles (AgNPs@PPE). The characteristics, anti-biofilm formation and cell toxicity of AgNPs@PPE were examined in vitro. Results: Absorbance at λ_max 372 nm which is related to the surface plasmon resonance, confirms the AgNPs@PPE formation. XRD pattern showed the face-centered qubic (fcc) crystalline structure of AgNPs. TEM images showed that spherical AgNPs size is ranged between 32 and 85 nm. The AgNPs@PPE showed inhibition effect against P. aeruginosa biofilm formation at 0.1 to 0.5 mg/ml concentrations. Cell toxicity assay showed that at 400 μg/ml, AgNPs@PPE were safe without a significant toxicity in L929 cell line. Conclusion: These data indicate that co-treatment of PPE and AgNPs@PPE significantly decreased the biofilm formation rate. Furthermore, no significant toxicity of AgNPs@PPE was shown against L929 cell line at 400 μg/ml concentration.

Background: Unique properties of graphene and its derivatives make them attractive in the field of nanomedicine. However, the mass application of graphene might lead to side effects, which has not been properly addressed in previous studies, especially with regard to its effect on the cell cycle. Methods: The effect of two concentrations (100 and 200 μg/mL) of nano- and microsized graphene oxide (nGO and mGO) on apoptosis, cell cycle, and ROS generation was studied. The effect of both sizes on viability and genotoxicity of the embryonic fibroblast cell cycle was evaluated. MTT and flow cytometry were applied to evaluate the effects of graphene oxide (GO) nanosheets on viability of cells. Apoptosis and cell cycle were analyzed by flow cytometry. Results: The results of this study showed that GO disturbed the cell cycle and nGO impaired cell viability by inducing cell apoptosis. Interestingly, both nGO and mGO blocked the cell cycle in the S phase, which is a critical phase of the cell cycle. Upregulation of TP53-gene transcripts was also detected in both nGO- and mGO-treated cells compared to the control, especially at 200 μg/mL. DNA content of the treated cells increased; however, because of DNA degradation, its quality was decreased. Conclusion: In conclusion, graphene oxide at both nano- and micro-scale damages cell physiology and increases cell population in the S phase of the cell cycle.